Hard-rubber articles.



Q PATENTED SEPT. 25, 1906.

w. R. SINE.

HARD RUBBER ARTICLES. APPLICATION FILED JAN.27,1906.

UNITED STATES PATENT OFFICE.

Specification of Letters Patent.

Patented Sept. 25, 1906.

Application filed January 27,1906. Serial No. 298,27-

process hereinafter described, and particu-- arly pointed out in the claims.

In the accompanying drawings, Figure 1' re resents a cross-sectional view of a mold in w 'ch the article to be vulcanized is placed, such figurerepresenting the objectionable features which my present invention is designed to overcome. Fig. 2 re resents a fabric of tubular form frictione orsaturated with hard-rubber compound after bein subjected to one step in my recess, and ig. 3 represents the fabric of ig. 2 covered with therubber compound and showing it in the mold undergoing the final step in my improved process.

In Figs; 1 and 3 the mold is shown at A, the fabric at B, and the rubber coatings at C. Fig. 1 shows how the linin has become pinched at the joint of the mol s, and Fig. 3 shows the perfect operation due to the present process. 1'

In ex erimenting u on the invention shown in etters Patent No. 785 ,234, granted to me on the 21st of March, 1905, I found difficulty, due tothe fact that when the saturated fabric was placed in the mold for vulcanization where the article being manufactured was tubular in cross-section the flexibility of the saturated fabric caused bucklin at the joints of the mold, and thus forme protuberances which penetrated the rubber compound intended to cover the fabric, these protuberances showing on the finished article in a line of the ex osed fabric. der to overcome this, take the saturated fabric after it comes from the rolls, out it into the shape required, and place the blank thus formed around the mandrel, with preferably some of the rubber compound between the mandrel and the fabric to form the inner lin- In or ing ,of rubber, and then subject the article thus partially formed to vulcanization, preferably in a dry vulcanizer, sufiicient to stiifen or harden the blank. This enables the proper handling of the blank in the further operation. The outer layer of rubber compound is then placed around the blank without danger of said blank changing its shape, and the article is then laced in the mold and vulcanized. While t is treatment is particularly necessary where the rocess is carried out in connection with tu ular articles, it is of very great advantage in all classes ofarticles made according to this process, as it prevents dis lacement of the article in the mold, as wil frequently follow where the flexible blank is used without the hardening process.

. It will be understood from the above that the coatin which is applied to the stifiened blank is of hard-rubber compound."

' What I claim isl.' The process herein described consisting in taking a fabric saturated'or filled with the rubber compound, subjecting this fabric to a hardening or stiffen ng treatment to permanently harden it, applying the outer layer of rubber compound to the stiffened fabric,

placing the permanently hardened or stiffened fabric with the layer thereon within a suitable mold and vulcanizing, substantially as described.

' 2. The process hereinbefore described consisting in taking a fabric saturated or filled with a hard-rubber compound, subjecting the said fabric toa hardening or stiffenin treatment to permanently stifien it an while maintaining the shape in which, it is stifi'ened ap lying "hard-rubber material thereto capa le of hardening and: then sub jecting the whole to a vulcanizing action, substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

WILLIAM R. SINE;

Witnesses:

HENRY E. Ooornn, R. E. ()URAND. 

